Year Percent 1950 29.19505 1955 27.00854 1960 25.84587 1965 26.47789 1970 28.58282 1975 29.96822 1980 31.04173 1985 31.54284 1990 31.20135 1995 30.87883 2000 29.55974 2005 26.67481 2010 25.19676 2015 25.20783 2020 25.56943 2025 26.13505 2030 26.06932 2035 24.53749 2040 23.58538 2045 23.47785 2050 23.44351 2055 23.98485 2060 24.15832 2065 23.83526 2070 23.30658 2075 22.92833 2080 22.80755 2085 22.85243 2090 22.85561 2095 22.65105 2100 22.29268